Remote control system



Sefit. 28, 1937. F. P. GOHOREL ET AL 2,094,151

REMOTE CONTROL SYSTEM Filed me 5, 1935 v s. Sheets-Sheet 1 INVENT OR. FERNAND PIERRE GOHOREl RAOUL LAFON FIG. I

ATTORNEY.

Sept. 28, 1937. F. P. GOHOREL ET AL REMOTE CONTROL SYSTEM Filed June 5, 1935 s Sheets-Sheet' 2 IINVENTOR. FERNAND PIERRE GOHOREL RAOUL LAFON ATTRNEY.

Sept. 28, 1937. F. P. GOHOREL ET AL 2,094,151

REMOTE CONTROL SYSTEM v Filed June 3, 1955 3 Sheets-Sheet 3 INV ENT OR.

ATTORNEY.

FERNAND PIERRE GOHOREL RAOUL LAFON Patented Sept. 28, 1937 UNITED STATES PATNT OFFICE REMOTE. CONTROL SYSTEM Application June 3, 1935, Serial No. 24,762 In France June 12, 1934 14 Claims.

The present invention refers to the remote control of. apparatus by currents of voice frequency, and is more particularly applicable to the transmission to a distance of controls or signals between two stations which can be connected together through the medium of automatic or manual switching apparatus, by means of circuits which may or may not be employed for other purposes, such as telephony or telegraphy, for example.

One of the characteristics of the invention resides in a remote control apparatus comprising the following elements: (a) a voice frequency current emitter arranged to send, either automatically or hand operated (keyboard or automatic telephone dial, for example), signals of convenient number and duration; (b) one or more receivingstations each comprising a voice frequency current receiver acting upon a recording apparatus arranged to produce a control or signal according to the code of the signals received; (c) one or more lines, telephonic or otherwise, which can be connected together for the purpose of connecting a transmitting station to a receiving station; ((1') means allowing of the putting into play, automatically or not, of the transmitting apparatus when the connection between a receiving station and a transmitting station is established, and this during the time necessary for the transmission of the signals, the connecting lines being rendered available for another use (telephony for example) when the transmission of the signals has been finished.

Another characteristic of the invention lies in a transmitting apparatus such as previously described but arranged to send first the controls necessary for the establishment of the connection between the transmitting and receiving stations, and then the voice! frequency current signals intended to produce the control or signal desired at the receiving station.

Another characteristic of the invention lies in the application of, the preceding apparatus to the r direct connection of a telephone or telegraph transmitting station to a secondary receiving station connected to a secondary exchange over the lines of one or more telephonic or telegraphic 'networks, either public or private; the transmitting station being arranged to send pulses of voice 50 frequency current over the telephonic or telegraphic connection established by the lines of the network between the transmitting station and the exchange, so as to bring about the orientation of the selectors of the secondary exchange 55 and thus to complete the telephonic or telegraphic communication between the transmitting station and the secondary receiving station. The connection of the lines in the network may be established either by means of an operator or by automatic switches, or partly by both of these methods of connection; in the case of automatic connection the transmitter of the transmitting station may be arranged to produce first the establishment of the main connection and then the establishment of the local connection in the secondary exchange.

Another characteristic of. the invention lies in an entirely automatic transmitting apparatus arranged to send, first, series of impulses over a telephonic or other line in order to bring about the connection of the latter to a receiving apparatus, and then other series of impulses to allow of the identification at the receiving station of the transmitting station, and finally to receive from the latter a particular communication; the transmitting apparatus being adapted so as only to send the identification impulses when the connection with the receiving stationis definitely established. In addition, the said transmitting apparatus may send one or more codes of connection signals to bring about the connection of the transmitting station to one definite receiving station among many receiving stations, and one or more codes of voice frequency signals to record one or more communications at the receiving station; the particular code of connection signals or of Voice frequency signals being determined by the nature of the communication to be transmitted.

One further characteristic of the invention lies in the application of an automatic transmitting apparatus such as the above to the automatic communication at a distance of various incidents (theft, fire, etc.). The invention covers .in particular, in this case, the use of an apparatus comprising: (a) an automatic transmitting apparatus, such as described above, situated at the transmitting station and capable in case of emergency of being connected to a primary line (telephonic for example) united to a central exchange; (2)) a receiver situated at the station where the signal is to be received, and capable of being connected either temporarily or otherwise transmitting station at the receiving station and to record a definite communication.

Also the said apparatus may be arranged so that the connection between the transmitting and receiving stations can be broken automatically as soon as the desired communication has been transmitted, so as to disengage the connecting lines, and to allow the receiving station toreceive a communication from another transmitting station; in this case the receiver is associated with one or more recorders which register the communication (after the disengagement of the line) either by visible signals, by marking on a tape, or by both methods simultaneously.

We will now explain the Working of difierent applications of a remote control apparatus in the spirit of the invention, by means of some not exclusive examples, referring to the attached diagrams which represent in Figure 1, a method of realizing the electric circuit of a transmitting station comprising a transmitter of voice frequency current;

Figure 2, another method of realizing the electric circuit in which a group of transmitting stations use a common voice frequency transmitter;

Figure 3, the electric circuit of a receiving equipment in a secondary exchange, together with a connecting line allowing of direct connection with stations attached to this secondary exchange;

Figures 4, 5, 6, and '7, a method of realizing an automatic transmitting apparatus;

Figure 8, the electric circuit of a receiving station adapted for use in connection with an automatic apparatus.

We will consider first a station such as that of Figure 1, connected by conductors 40 and 4| to conductors 42 and 43 ending in an exchange 39, which may be the case of a subscribers station connected to a public automatic exchange.

Let us suppose that a person at the said station wishes to enter into direct communication with a station attached to a secondary exchange (such as a private automatic exchange), the said exchange having a receiving equipment like that of Figure 3, and that the communication is to be efiected without the intervention of a third person.

The calling subscriber unhooks his handset, and by the operation of the switchhook loops the line at his station.

By operating his calling dial, he then brings about the numerical operation of automatic switches in the public exchange 39, so as to connect with conductors 61 and 68 leading to the secondary exchange, all in accordance with the current practice in automatic telephony.

At the end of the dialling, the final switch or connector in the public exchange 39, Figure 3, sends periodic ringing current over the trunk line conductors 61 and 68. This ringing current is received by the relay I2 in the circuit: conductor 68, armature Hi and its resting contact, armat1u-e I 9| and its resting contact, condenser 69, relay winding I2, armature H2 and its resting contact, and conductor 6?.

0n the reception of ringing current during the first ringing period, the relay I2 energizes and remains so during the'whole duration of the said period. By its armature I2I and its working contact it closes the circuit of the relay I l: earth, armature I2I and its working contact, armature I32 and its resting contact, the Winding of relay I4 and the battery. Relay I4 energizes and by means of its armature ME and its working contact prepares its locking circuit through relay I9. When the relay I2 releases at the end of the first ringing period, the relay I3 energizes in series with I4 and prepares the energizing circuit of the relay It, through its armature I32 and working contact. 7

On the reception of ringing current the second time, relay I2 responds again and the relay I6 energizes in the circuit: earth, armature I2I, working contact of armature I32, armature I52 and resting contact, the winding of relay I6 and the battery. Relay I9 energizes, and, through its armature I6I and working contact, prepares its locking circuit in series with the relay I5. At the end of the second ringing period the relay I2 releases and the relay I5 energizes in series with the relay I6 in the circuit: battery, winding of relay I 6, winding of relay I5, armature I6 I armature I92, and earth. Through its armature I52 relay I5 breaks the circuit of the armature I2I of relay I2; through its armature I5I and working contact it closes the circuit of the relay I9: conductor 68, armature III and its resting contact, armature I5I and working contact, armature IBI, armature 2M, the upper winding of re lay I9, armature I A2, to conductor 61.

The line conductors 6'! and 68 are now bridged by the relay I9, which has the known effect of stopping the transmission of ringing current by the connector, and the completion of a talking connection from the conductors 49 and 4! of the calling station to the conductors 61 and 68. The talking connection, as is Well known, includes inductive connections which prevent the transmission of loop impulses beyond the exchange 39.

Relay I9 in energizing breaks, through its armature I9I and resting contact, the circuit of relay I2; through its armature IBI and working contact it prepares a locking circuit; through its armature I92 and resting contact it breaks the looking circuit of relays IS, i4, i5, and I6, which deenergize; through its armature I93 and working contact it maintains the left-hand winding circuit of the relay 2I closed through the leads I0 and II ending in the private exchange, the circuit having been first completed by the armature I 43 of the relay I4; by its armature I92 and working contact it closes the relay circuit I'I: earth, armature I92 and working contact, armature H3 and resting contact, armature 22I and resting contact, the winding of relay I'I, battery. Relay I1 is a time delay relay of a type such that it only closes its contact after a definite lapse of time. If, for any reasons, the subscriber does not continue the calling process, but replaces his handset, the relay II, after a certain time, operates armature I'II which completes the circuit of relay I8. Relay I8 is also a time relay of such a kind that after a definite lapse of time it energizes, opening by its armature IBI and resting contact the circuit of relay I9, which deenergizes, thereby disconnecting itself from in bridge of conductors 61 and 68.

The said relay I 9 also opens, through its armature I93, the left-hand winding circuit of relay 2 I, thereby freeing the trunk line comprising the leads "I0 and II; by its armature I92 and working contact the relay I 9-breaks the circuit'of relay II,

which deenergizes, opening in its turn the circuit of relay I9, which releases. All the apparatus of the secondary exchange, as well as the receiving equipment, Fig. 3, is now in normal position, the line Ell- 58 is free, and a new call can be received from the public exchange 39.

In, addition, by its armature I12, relay I'I closes the circuit of the calling lamp Ap at the manual switchboard. The operator can listen over the jack J in order to enter into conversation with the calling subscriber and if necessary to direct the communication to another called subscriber of the private exchange.

We will now suppose that the calling subscriber continues the connection operations. Relay i9 being energized, the leads 1i] and 'II ending in the automatic secondary exchange have been loopedv through the left-hand winding of relay 2!. Therefore *the automatic switching equipment in the said secondary exchange is ready to efiect a connection with a station of the same exchange.

By its armature I94 and working contact the relay I9 also completes the circuit of the leads 6'!68 through the winding I2 of the alternating current impulse receiver.

The calling subscriber, having noted by listening in his receiver that the transmission of ringing current from 39 has ceased, that is to say, that his first connection has been established, works the keys 3! at his station. This opens the contact 3 I33 and closes 3 !32. This results in the relay Ill being energized at each opening of the impulse contacts 3! through the circuit: earth via the equipment of 39, conductor v43, closed contact 38, Winding of relay I0, contact 323I, contact -34, lead 40, lead 42, and battery via the equipment of exchange 39. Relay I0 attracts its armature IIlI, short circuits, releases, and becomes activated again. It acts therefore in an oscillatory manner. Thus at each opening of the impulse contacts 31 a pulse of alternating current emitted by relay I0 is sent over the line, through the exchange 39 to the leads 6'! and 6B, and is received by the winding 12 of the input transformer of a thermionic amplifier through the circuit: lead 68, armature III and resting contact, condenser Tl, armature 2!! and resting contact, winding I2, armature 2M and resting contact, condenser 18, armature I54, armature H2 and resting contact to lead 6'5.

The alternating current impulses received by the Winding l2 induce impulses in the winding 13, which are amplified by the valve I9, and rectified by the rectifying system 16, whereby they operate the relay 23, which by its armature 232 and resting contact breaks the line circuit of leads l0 and II. It can be seen that for every impulse transmitted by the calling subscriber there is a corresponding opening of the line running to the private automatic exchange. The said calling subscriber is thus able to call any of the subscribers attached to the private exchange.

On the receipt of the first numerical impulse, relay 23 closes by its armature 23! the circuit of relay 22: earth, armature 23! and working contact, winding of relay 22, and battery. Relay 22 being excited closes, by its armature 222 and working. contact, its locking circuit: battery, winding of relay 22, armature 222 and working contact, armature I92 and working contact, to earth; by its armature 22! it breaks, through its resting contact, the circuit of relay I'!, which deenergizes, and by its working contact closes the circuit of relay I8: battery; winding of relay I8, armature 22! and Working contact, armature 2 I3 and resting contact, armature I92 and working contact, to earth. As has been already explained, relay I8 is a time delay relay. If the subscriber with whom the calling person wished to communicate does not'respond, relay I8 opens its contact I8! after a certain time which corresponds to the time necessary to effectdialling and ringing, which releases all the apparatus and the calling line as has been already ex plained. v

In the case in which, the calling person having finished the impulsing, the call is completed and the subscriber called replies, the latter produces an inversion of polarity, over the leads I0 and I! from the private exchange, which energizes the polarized relay 2!. By its armature 2I2 and working contact it completes a new locking circuit for relay I9. By its armature 2I3 it breaks, through its resting contact, the circuit of relay I8, and closes through its working contact the circuit'of relay 2G: battery, winding of relay 2!), armature 2I3 and working contact, armature H92 and working contact, to earth. Relay 20 energizes, closes through its armature 202 its locking circuit, and breaks by its armature 2c! the first energizing and locking circuit of relay I9.

By its armatures 2! I and 2M relay 2! connects leads 6'! and SBwith leads H! and H. The calling person is then in communication with the called subscriber. They may enter into conversation or code signals may be transmitted over the line.

At the end of the conversation, or of them cording of signals, a disconnect operation is performed on the line of the called subscriber, as by hanging up, thereby producing a new reversal of the battery through the leads I0 and 7!.

V The polarized relay 2! deenergizes. By its armature 252 it breaks the locking circuit of relay !9 thus freeing the line ESL-58 to the public exchange 39. Relay I9 deenergizes and by its armature I93 breaks the left-hand Winding circuit 1 of relay 2B; the line !0'!l leading to the private exchange is released. By its armature I92 relay I9 breaks the circuit of relay 22 winch is deenergizedas well as cutting off the supply of the polarizing winding of 2 I. Relay 2! in deenergizing reconnects, by its armatures 2!! and 2M, the leads 61 and 68 with the winding 12 of the impulse receiving apparatus.

All the parts of the receiving equipment of the secondary exchange as well as the line leading to the public exchange, and that leading tothe private exchange, are now free and in a position to receive or transmit a new call.

On the replacement of the handset by the person calling the line 42-43 leading to the public exchange is freed in its turn.

We will now explain the method of establishing a direct connection, in the case where a group of calling stations include a voice frequency transmitter which can be connected to any one of the said stations. On consideration of Figure 2 it is seen that the calling station P is connected to a private exchange 8%], which may be an automatic exchange.

By dialling a certain digit the calling person can operate a selector switch in the exchange 88 and connect his line with the transmitter E. At the end of this operation, relay 24 of the transmitter E energizes over the calling line and by its armature 242 and Working contact, closes the circuit of relay 25: battery, non-inductive winding of relay 25, armature 2 32 and working contact, winding of relay 25, to earth. By its armature 2M and working contact relay'24 prepares the seizing and impulsing circuit of line 4445, which in this case is connected to line 4243 of the public exchange 39in place of line 4il4!. Relay 25, becoming energized in the circuit indicated, completes through its armature 25! and working contact the loop on the output line: lead 42, lead 44, lower right-hand winding of relay 3!], lower right-hand winding of relay 29, inductance 28, armature 24! and working contact, armature 25! and working contact, lead 45, to lead 43.

The apparatus of public exchange 39 is thus placed in a condition to receive a call. By its armature 242 and working contact relay 25 completes the circuit of the polarization windings of the polarized relays 29 and 39; by its armature 254 and'working contact it prepares the energizing circuit of relay 2%; by armature 253 it closes a holding circuit for the operated selector in exchange 89. The calling subscriber, having received dial tone, works his calling dial in ac cordance with the proper digits, thereby operating automatic switches in exchange 39 to effect the connection of his station with the equipment of Figure 3.

It will be noticed that the energizing windings of the polarized relays 29 and 39 have been placed in series with the loop circuit of the line; the direction of the current in each of these is such 44 and 45, for example a battery on 44, relay 29 on the other hand will not be influenced, and vice versa. 7

Let us suppose then that relay 3!] energizes. By its armature 393 and working contact it closes the circuit of its locking winding, by its armature 394 and working contact it short-circuits. its energizing winding; by its armature 39! and working contact it completes the loop circuit which is found open through armature 392 and its resting contact; by its armature 365 it prepares a circuit for the alternating current impulse relay 2i.

The breaks made by the dial of station P on the line 8!82 will result in the intermittent deenergizing of relay 24 of E to which the line is connected through the exchange 89. On the reception of the first impulse relay 24 deenergizes and through its armature 242 and resting contact completes the circuit of relay 2%; earth, armature 242 and resting contact, armature254 and working contact, inductive and non-inductive windings of relay 265, to battery (relay 25 whose winding is short-circuited is thus rendered slow to deenergize and remains energized during the whole train of impulses). On becoming energized, relay 26 closes, by its armature 252 and working contact the impulsing circuit: lead 44, armature 262 and working contact, armature 292 and resting contact, armature 24! (which vibrates during the impulses), armature 25! and working contact, to lead 45. 7

Relay 26 remains energized in series with relay 25 during the whole train of impulses. It can be seen that at each deenergization of relay 24 a break is produced, by armature 24!, on the line leading to exchange 39. The subscriber P thus accomplishes the orientation of the apparatus of the said exchange, and when the dialling is finished ringing current is sent over the leads 6'! and 69 and is received by relay !2 of the apparatus in Figure 3, the operations taking place as they have been described in the preceding case. The line is finally looped with relay !9 which cuts off the ringing current at the exchange 39, and causes the reversal of polarity in the leads 42-43 and 4445.

At the end of the dialling by the subscriber for the establishment of this second connection relay 24 remains energized as does relay 25.

As soon as the polarity reverses in the line leads 44 and 45 the relay 29 energizes. By its armature. 293 and working contact it closes the circuit of its locking winding; by its armature 294 and working contact it short circuits its energizing winding and loops the line through the inductance 28; by its armature 292 and resting contact it breaks the first loop, circuit of the line, and .by its armature 29! and working contact, it prepares a continuous loop circuit which becomes necessary during the working of relay 24.

The calling subscriber having ascertained, by listening in his receiver, that the call has reached the private exchange of Figure 3, proceeds to a third dialling operation with the object of putting himself directly in communication with a subscriber attached to the private exchange.

The impulses are again'received by relay 24, but this time the working of the latter is without effect on the apparatus of 39, its armature 24! and working contact being short-circuited by the operated armatures 39! and 29!. 'However, when on the reception of an impulse relay 24 deenergizes, it completes the circuit of relay 2'!: earth, armature 249 and resting contact, armature 295 and working contact, armature 305 and working contact, winding of relay 2'!, to battery. Relay 2'! becoming energized connects by its armatures 27! and 272 and their working contact the lines 95 and 86 carrying an alternating current of voice frequency with the leads of the line 44 and 45.

Thus at every deenergization of the relay 24 there is a corresponding energizing of relay 2'! and the transmission over the line of an alter nating current impulse.

The said impulses are transmitted through the exchange 39, are received by the apparatus of Figure 3, and effect the establishment of an internal connection as has been described in the preceding case. At the end of this dialling the calling subscriber finds himself in connection with the required station.

The freeing of the apparatus in the called exchange takes place as has already been shown; at the calling exchange, on the replacement of the'handset of the person calling, relay 24 deenergizes, causing relay 25 to deenergize after a short time, which opens the circuit of 26 and the locking windings of 29 and 30.

The whole apparatus comes to rest, and the equipment E can be taken up by a new call.

The idea of connection through one or more exchanges has been described in the above examples, we will now show the action of an automatic receiving apparatus for impulses capable, on receiving a call, of effecting a visualand audible signal, allowing in particular of the determination of the origin of the call.

Theperson calling having finished the preced ing operations, the apparatus of the public exchange has prepared the connecting circuit, and the call is extended to the apparatus of Figure 8. The ringing current transmitted over the leads 81 and 88 is received bythe upper winding of relay 4%, which energizes. By its armature 462 and working contact it closes the circuit of its locking coil: earth, armature 47! and resting contact, armature 264 and Working contact, lower winding of relay 49, to battery; by its armature 46! it prepares the energizing circuit of relay 4?; and by its armature 463 and working contact it closes the circuit of the rotary magnet of finder C'l:

earth, armature 4H and resting contact, armature.463 and working contact,'contact 95! of the electromagnet, winding of electromagnet B5, and battery. The seeker is started in free rotation carrying the wipers 89, 99 and 9 I.

When Wiper 99 arrives at a contact segment such as 99', corresponding to. a free registering receiving apparatus, the said wiper finds a battery and the energizing circuit of relay 41 is completed: earth, armature 49! and working contact,

- the two windings of relay 41 in series, wiper 99,

bank contact 99, inductive and non-inductive windings of 59 in parallel, armature 5|! and resting contact, contacts 92 and 92' of the switch C2. in its resting position, armature 582 and resting contact, inductive and. non-inductive Windings of 51 in parallel, to battery. Relay 41 in energizing breaks, by its armature 4H and resting contact, the circuit of the electromagnet 65, arresting switch Cl; by its armature 4H and working contact it completes its locking circuit through the lower winding; by its armatures 412 and 415 and their working, contacts it reconnects the leads 81 and 99 with the Wipers 89 and 8|; by its armature 41! and resting contact it breaks the circuit of the locking winding of 49, which deenergizes;

Furthermore in the same circuit as 41, relays- 69 and 51 become energized. Relay 69 on energizing connects by its armatures 69! and 995 and their working contacts the. wires of line 81, 88, to relay 52. The emission of the ringing current from exchange 39 comes to an end, and relay 52 becoming energized completes the circuit of leads 81 and 88 through the winding 95 of the input transformer of the receiving apparatus for the alternating current impulse By its armaturesv 692, 594 and 996 and their working contacts relay 69 connects the controlling circuits of switches C3, C4, C5 with the bank contacts of switch C2.

Relay 51 on energizing closes, by its armature 5H and working contact, the circuit of the time delay relay 59.

The adjustment of the said relay 58 is regulated so that its armature 582 is only operated after the time necessary for the reception and recording of a call has elapsed. After this interval it operates its armature 592, opening the energizing circuit of relays 41, 69 and 51 and by the latter its own circuit. The apparatus returns to its rest condition and the line from the public exchange is disengaged.

By its armature 512, relay 51 completes the energizing circuit of relay 59; earth, armature 512 and working contact, bank contact 91, wipers of C2, bank contact 95, lower winding of 59, contact 6H of the electromagnet 6|, electromagnet GI, and battery. I

The resistance of the electromagnet BI is such that it is not excited in series with 59, which latter, however, becomes energized. By its armature 59! and working contact, relay 59 closes the circuit of the electromagnet 63 of the time stamp 98: earth, armature 512 and working contact, bank contact 91, wipers, bank contact 96, armature 59| and working contact, bank contact 99, wipers, bank contact I99, winding of 63, to battery. The electromagnet attracts its armature l9l producing an impression of the hour and the date on the tape I92.

By its armature 594 and Working contact, relay 59 completes the circuit of the electromagnet 62 of the mechanism for moving the tape. By its armature 593 and working contact it places a direct earth on the electromagnet iii which attracts its armature thus breaking the circuit of 59, which deenergizes. Armature 595 opens its contact and the wipers of C2 pass to the second position.

Electromagnets 92 and 69 are deenergized and the tape i 92 is advanced, being pulled forward by the rollers associated with 62.

Suppose that the calling subscriber, having ascertained that the transmission of the ringing current from the exchange 39 has ended, continues dialling with the object of indicating, by visual recordings, his own signal or code number, and of exciting an alarm. The transmission of impulses is then made in alternating current, as has been shown in the previous examples. The said impulses received by the leads 81 and 98 are transmitted by the circuit: lead 81, armature 413 and working contact, Wiper 89, bank contact 99, armature EM and working contact, input Winding 95 of amplifier A2, armature 695 and working contact, bank contact 9!, wiper 9i, armature 412, and working contact, and lead 89, to the grid of the amplifier; are amplified and retransmitted through induction coil 93; and after passing through the rectifier 94, they activate the impulse relay 53.

On the reception of the first impulse, relay 53 closes, through its armature 531 and working contact, the circuit of relay 54 which becomes energized. By its armature MI and working contact, relay 54 closes the energizing circuit of relay 55: earth, armature 54! and working contact, armature 55| and resting contact, the lower winding of 55, to battery; by its armature 542 and working contact it closes the circuit of the stepping electromagnet 96 of the recording drum 95 which attracts its armature causing the said drum to advance one space. Relay 55 on energizing completes, by its armature 553 and working contact, the circuit of relay 56, which becomes energized; by its armature 554 it closes the circuit of the electromagnet 6| of switch C2 which attracts its armature.

Relay 55 is found to be short cir'cuited every time 54 deenergizes, and being thus rendered slow locks itself throughout the whole of the reception of the impulse train.

By its. armature 54!, relay 54, on the reception of each impulse of the first train of impulses, causes the step by step advancement of the switch C5 of the lamp'recorder over the circuit: earth, armature 5M and working contact, bank contact I94 of C2, wiper of C2 in the second position, bank contact E93, armature 595 and working contact, winding of electromagnet 59, and battery.

It can be seen that, at the end of the first trainof impulses, the switch C5 and the number drum, 95 will have advanced a number of steps equal to the number of impulses received. When the impulses cease relay 55 deenergizes.

By retracting its armature 554, relay 55 breaks the circuit of the electromagnet 6! which releases its armature, stepping the wipers of C2 to the third position. The retraction of armature 554 of relay 55 also closes a circuit for magnet 52, since the slow acting relay 55 remains in operated position for an instant after 55 falls back. Relay 55 on retracting its armature 553 closes a circuit for magnet 64. The operation of magnet 64 prints on the tape H92 the digit set up on number drum 95. Shortly after relay Q55 deenergizes, relay 55 deenergizes, breaking the circuits of magnets 64 and 52. The latter magnet advances the tape I52 when it deenergizes.

The deenergization of also restores the number drum by completing the circuit: armature 553 and resting contact, armature 56I, resting contact, ofi normal contact I5, interrupter contact of electromagnet 66, magnet 66, and battery. Magnet 66 vibrates its armature, whereby drum 95 is moved forward automatically to its position of rest, in which it breaks the contact I95 causing it to stop at the said position.

It can be seen that after the reception of the first impulse train, the corresponding number has been printed on the tape I2, and the switch C5 of the lamp recorder occupies a position corresponding to the number of impulses received. Also the circuit of electromagnet 49 of switch C4 has been prepared to receive the impulses of relay 54 as has been explained in the case of the advancement of switch C5.

The impulses of the second train take the wipers of the said switch C4 to the position corresponding to the number of impulses emitted. At the end of the second train, roller 95 prints the corresponding digit as has been explained in the preceding case, and switch C4 stops. On the deenergizing of relay 55, switch C2 advances to the fourth position. The third train of impulses will now be received by the switch C3 which takes up a position corresponding to the number of impulses received. The third digit is printed on the tape I02.

It has been assumed in the example given that the recorder is arranged to receive calling signals of three digits. It is clear that the number of switches such as C3, C4 and C5 could be increased by providing control circuits attached to the vacant contact segments of switch C2, and one could thus receive calls of four digits and upwards.

After the reception of the third train of impulses relay 55 deenergizes causing the advance of switch C2 to the fifth position. The circuit of relay 5| is completed through: earth, armature 512 and working contact, contacts and wipers of C2 in the fifth position, armature 603 and working contact, winding of 5|, and battery. Relay 5I in energizing locks itself at its armature I 5I2 and closes, by its armature 5| I, 5I3 and 5I4 and their working contacts, the circuits of the signal lamps of the recorder, which thus indicate the number of the calling station.

By its armature 5|5 and working contact it I closes the audible alarm circuit including bells 55' such as I 01; by its armature 5 I 6 and Working contact it closes the circuit of relay 5| which energizes, breaking, by 5|2 and resting contact, the circuit of relays 41, and 51, which deenergize. By its armature 5 II and working contact it closes its locking circuit through the middle wipers of C3, C4 and C5.

Relay 41 opens the line circuit to the public exchange 39; the said line is free and can receive a new call.

Relay 50 deenergizing frees the call recorder, and prepares the return circuits of switches C3, C4, and C5, for advancing said switches to their resting position. Relay 5'! opens by its armature SH and working contact, the circuit of time relay 58. By its armature 512, and resting contact, it completes the circuit of relay 59: earth, armature 572, resting contact, bank contacts I08 and I99 of C2, upper winding of 59, contact 6| I of electromagnet 5|, electromagnet BI, and battery.

By its armature 593 and working contact, the

relay 59 closes the circuit of electromagnetfil which attracts its armature and at 6| I breaks the circuit of 59, which deenergizes, but becomes energized again as soon as contact 6 is reclosed. It can be seen that the switch C2 automatically advances, controlled by relay 59; when the said switch reaches its resting position the circuit of 59 is broken.

During the restoration of C2 relay 59 transmits impulses to magnet 62 at armature 592. Magnet 62 accordingly advances the tape I62 by means of rollers III and'IIZ.

When the call has been noticed, the operator at the exchange Works key I, I 3 which deenergizes relay 5I, which by its armatures 5| I, 5I3 and 5I4 and their resting contacts, completes the circuits for the automatic return to the resting position, of switches C3, C4 and C5. When the said switches have all three returned to their resting position, the locking circuit of relay 5| is opened, and this relay deenergizes.

The call recording apparatus is now in a position to receive and record a new call.

In the explanations referring to the working of the apparatus which has just been described, it has been assumed that the control impulses were sent out by the calling person by means of a dial. It is clear that one could use any apparatus capable of sending a convenient code of impulses, without the action of the system being affected, and in particular could use the automatic impulsesending apparatus shown in Figures l, 5, 6 and '7, whose working will now be explained.

Referring to Figure 4, in which only those parts of the apparatus necessary for understanding the invention have been included, it is seen that the apparatus comprises five'cams II], II, I2, I3, and I5 mounted on the same shaft.

These cams may be set in rotary motion by a driving system not represented, whose velocity is regulated by the governor I5. The impulse cam I6 is also set in motion by the same driving system.

In the rest position the compound arm 20 of the armature of the polarized relay I9 is engaged in the notch 24 of the disc I0, thus holding the mechanism stationary.

' If now Figure 7, which represents the scheme of electrical connections of the impulse sender, is examined, it is seen that a certain number of contacts such as 25 and 25 are distributed at the various points from which a call'might have to' be sent. Leads 27 and 28 go to an ordinary telephone station and leads 29 and 39 to a public automatic exchange. Furthermore, the impulse sending system may be inserted in the telephone line by means of a quadruple jack represented in Figure 7.

Let us suppose that a person works the calling button 25. The following circuit is completed: lead 29, spring 3|, spring 32 (of cam II in Figure l) closed contact 25, winding of relay I9, impulse springs I'II8, and lead 30.

Relay I9 is energized through the equipment of the public exchange and attracts its armature in the position shown in Figure 6 in full lines. Arm 29 is thus disengaged from the disc Ill and the mechanism is set in motion, including cams Ill, II, I2, I3 and I4, the governor I5 and the impulse cam I 5. Cam I2 works spring 31 and by its contact 39 short-circuits relay I9; after a short interval, necessary for putting the apparatus of the exchange in a position to receive the call, the cam II operates its contact springs. By its spring 34 it breaks at contact 33 the circuit of the station connected to leads 2? and 28; by its springs 34 and 35, it loops leads 29 andiifl with the calling apparatus; by spring 332 it breaks the circuit of the calling buttons, at contact 3i.

Line 29-30 being in a position to receive the call, cam I3 operates spring 39 and opens the circuit of its resting contact 39. Thereupon the impulse springs lll&l are no longer short-circuited and under the influence of cam it, can send, during the whole time that the control spring M of cam is is in the notch as, a series of impulses which will be received by the public exchange.

Cam l3 continues its rotation and the part is again operates the control spring 4 1, and by springs 39 and 4E! short circuits the impulse springs i1 and I8. After a short interval a new notch in cam I3 effects the transmission of an other train of impulses, as has been shown.

It can be seen that during half a revolution of cam l3, for the shape represented, by way of ex ample, three trains of impulses will have been sent over leads 29 and 86, the said impulses effecting the orientation of the apparatus of the exchange to complete the call to the subscriber dialled.

When the cams have rotated through half a revolution, the compound pin 46 of cam it comes to rest on arm 22 of the plate 2i, which occupies the position shown in full lines in Figure 6, as has been shown. This holds up the mechanism and the cams stop. Spring El associated with cam I2 is released in notch cl which has taken up a position diametrically opposite to that shown in the figure. Polarized relay is is no'longer short circuited. Spring 44 now rests on the projecting portion 48 of cam l3.

' When the call is completed at the receiving station, it produces at the public exchange, reversal of polarity in leads 29 and 3&3. Polarized relay l9 again operates its armature and attracts parts 2| and 2%). 2i frees the pin 56, but its displacement is limited by which comes to rest against the cam ill. Under these conditions the arm 23 of the said part ill will not be able to engage the pin 46 placed symmetrically on the other face of cam 10, and the freed mechanisms are set in motion again and with them the cams. Cam l2 operates its spring 3? and short-circuits polarized relay l9. Cam l4! frees its spring 49, which comes to the cut-away portion of the said cam, which brings about the closing of the circuit of springs 4! and #52 and prepares an energizing circuit for relay 5%.

It can be seen that when, by the action of the profile of cam 83, spring 39 opens its circuit with contact 40, relay 59 is placed in parallel with the impulse springs II and i8.

At each opening of the said springs, relay 5!] energizes and by vibratory action of its armature 5| emits an impulse of alternating current.

The result is that this second series of impulses will be emitted as alternating current impulses and will be received via the public exchange at the private exchange called where it will effect the orientation of the alarm or call recording apparaus as has been explained in the preceding cases.

When the second impulsing has been finished, cam til having completed one revolution, the pin 52 comes to rest against arms 23 of piece 2i (Figure 6) in the position shown in dotted lines. The mechanism stops. Cam ll whose control spring is again opposite the incised portions, operates its contacts. The loop over the line 293@ is broken, and the circuit of the calling buttons is putinto action again. Polarized relay l9 returns to its conditions of rest, and '20 engages in the notch 2t holding the mechanism looked after freeing the pin 52 by arm 23 of piece 25. A new call can be sent over the line.

It will be noticed that the action of the mechanism is independent of the initial polarities of the line, one or other of the pins such as 46 being used at the moment of reversal of the current, the action remaining the same as that already described.

Having described the invention, What is considered to be new and is desired to be protected by Letters Patent will be set forth in the following claims.

What is claimed is:

1. A telephone substation comprising a calling device, impulse springs in said calling device adapted to be bridged across the line, a relay, means including oil-normal contacts of said calling device for causing said relay to be shunted around said impulse springs during the operation of the calling device, and contacts on said relay for short circuiting its winding.

2. In a repeater, incoming and outgoing lines, a line relay responsive to loop impulses received over its incoming line for repeating loop impulses over the outgoing line, and means controlled over said outgoing line for changing the circuits of the repeater so that said relay responds to loop impulses received over the incoming line by repeating alternating current impulses over said outgoing line.

3. In a switching system, an impulse transmitter, means for operating said transmitter to send trains of impulses of a particular character, automatic switches responsive to said impulses to partially establish a desired connection, means revertively controlled over the partial connection for altering the transmitter so that further operation thereof will produce trains ofimpulses of a diiferent character, and switches for completing the connection responsive to such last mentioned impulse trains.

4. In a switching system, a trunk line extending through a repeater to an automatic switch, means in said repeater for converting alternating current impulses to operate said switch into loop impulses, and means responsive to ringing current received over said trunk line for connecting up said converting means.

5. In a switching system, a trunk line extending through a repeater to an automatic switch, means in said repeater for converting impulses of high frequency alternating current into loop impulses to operate said switch, and means in said repeater responsive to a predetermined number of impulses of low frequency alternating current for connecting up said converting means. 6. In a switching system, a repeater, incoming and outgoing lines, means responsive to impulses of high frequency alternating current received over said incoming line for repeating loop impulses over said outgoing line, automatic switches responsive to said loop impulses tocomplete a connection and means in the repeater revertively controlled over said outgoing line responsive to completion of the connection for connecting together the said incoming and outgoing lines.

'7. In a telephone system, two automatic exchanges, automatic switches in the first exchange controlled byloop impulses to set up a talking circuit including an inductive connection, a trunk line leading to the second exchange adapted to be included in said connection, means for transmitting alternating current impulses through said inductive connection and over said trunk line to the second'exchange, switches in the second exchange controlled by loop impulses, and means for converting alternating current impulses into loop impulses to operate said switches.

8. In a telephone system, a repeater adapted. to transmit either loop impulses or alternating current impulses, means responsive to trains of loop impulses transmitted by said repeater for extending a connection, means responsive to the extension of said connection as far as it can be accomplished by means of loop impulses for automatically converting said repeater to the transmission of alternating current impulses, and means for further extending the connection responsive to alternating current impulses.

9. In a telephone system, a repeater adapted to transmit either loop impulses or alternating current impulses, trunk lines over which loop impulses can be transmitted, other trunk lines over which alternating current impulses but not loop impulses can be transmitted, means responsive to trains of impulses emitted by said repeater for setting up a connection by linking together a plurality of said trunk lines, and means effective when a trunk line over which loop impulses cannot be transmitted is linked into the connection for automatically changing over said repeater to cause the same to transmit alternating current' impulses.

10. The combination, with an automatic exchange, of a repeater controlled over a subscribers line for sending trains of loop impulses to said exchange, a line, automatic switches responsive to said impulses to connect with said line, a recorder on said line, means responsive to the completion of said connection. for altering said repeater so that alternating current impulses may be sent over the established connection to said recorder, and means for operating said recorder responsive to said alternating current impulses.

11. The combination, with an automatic exchange, of a plurality of lines that can be called through said telephone exchange, a plurality of recorders common to said lines, means responsive to the receipt of a call on one of said lines for connecting the same to an idle recorder, and means for transmitting alternating current impulses over the established connection to operate said recorder.

12. In a telephone system, a line, a recorder controlled over said line, a connector, a repeater, means including said repeater for transmitting loop impulses to operate said connector to connect with said line, means in the connector for sending ringing current over the line to said recorder, and means in the recorder for controlling the connector to cut off the ringing current and also for causing the connector to control the repeater and condition the same to transmit alternating current impulses through the connector to operate the recorder.

13. In an automatic impulse transmitter, means for transmitting a plurality of trains of impulses of acertain character, means automatically efiective after part of said trains have been sent for altering the transmitter so that the succe-eding trains will comprise impulses of a different character, and means for automatically restoring the transmitter to its former condition after all said trains have been sent.

14. In an automatic impulse transmitter, impulse springs intermittently opened and closed, a circuit, means including a cam for rendering said springs effective at spaced intervals to open and close said circuit, a relay having contacts for short circuiting itself, and means including another cam for bridging said relay around said contacts during certain of said intervals.

FERNAND PIERRE GOHOREL. RAOUL LAFON. 

